TEMPORARY SLOPE PROTECTION: COST VS. EFFECTIVENESS

摘要

Soil stabilization is a key concept in the realm of erosion control. As many construction sites are in the grading phase, slopes become exposed requiring temporary stabilization protection before homes, permanent landscaping or other enhancements are established to maintain compliance with the NPDES permit. Several products on the market provide sufficient coverage and protection. Performance correlates with the costs, as shown in a study conducted by Landscape Development, Inc. Varying products were shown to reduce the amount of soil lost on a typical 2:1 slope. However, performance is also dependant upon the area that needs protection, the type of soil, and the amount of time the protection is needed. Landscape Development, Inc. conducted a study in Santa Clarita, CA. Eight products and applications were tested on 92.9 square meters (1000 square foot), 2:1 slope panels during the heavy rain season of 2004-2005. The rains in this area accumulated to over 101.6 cm (40 inches) between October and May. The products and applications tested include straw blanket, blown straw with organic binder-tackifier, straw/coco blanket, coconut blanket, jute netting, wood fiber mulch and organic binder, a preblended stabilized fiber matrix (SFM) with two stabilizer components (a tackifier and cross link binder), and another stabilized fiber matrix (SFM) with one stabilizing component consisting of wood fiber mulch with polyacrylimide stabilizer. Four soil loss samples were taken over the course of the study. The weight of the soil lost was accumulated and used in comparing the performance of the varying products and applications. The blanket products performed better, overall, for retaining the soil on the slope face when compared for amount of soil lost per inch of rainfall. The cost comparison for all the products and applications showed comparable pricing when extended over the duration of the product/application's effective lifeline.